Materials Literature
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Codoping of Ga and N was utilized to realize p-type conduction in ZnO films using rf magnetron sputtering. The films obtained at 550°C on sapphire showed resistivity and hole concentrations of 38Ωcm and 3.9×1017cm−3, respectively. ZnO films also showed a p-type behavior on p-Si with better electrical properties. ZnO h…
The electrical conductivity and temperature coefficient of resistance of polycrystalline platinum nanofilms have been investigated experimentally and theoretically. The results show that these electrical properties have been greatly reduced mainly by grain boundary scattering. By applying the theory of Mayadas and co-…
The authors demonstrate that the electric conductivities of cubic and hexagonal boron nitride (c-BN and h-BN) thin films increased markedly by the in situ doping of zinc. The doped films were electrically semiconducting, and conductivities at room temperature increased from 10−8to10−2Ω−1cm−1 with increasing zinc conce…
When two or more crystals have the same structure except for the replacement or addition of one or a few (usually heavy) atoms, phase determination using isomorphous replacement can be resorted to. In most practical instances, the atomic form factor is a real number. When the absorption edge of an atom is close to the…
Abstract We consider a solution of the Cahn–Hilliard equation or an associated Caginalp problem with dynamic boundary condition in the case of a general potential and prove that under some conditions on the potential it converges, as t → ∞, to a stationary solution. The main tool will be the Łojasiewicz–Simon inequali…
Nanocomposites are a promising new class of structural materials for the mechanical components of microelectromechanical systems (MEMS). This paper presents a detailed theoretical investigation of the utility of carbon nanotube-reinforced composites for designing actuators with low stiffness and high natural frequenci…
The authors report on the high-performance metal-semiconductor-metal planar photoconductors based on unintentionally doped homoepitaxial diamond thin films. The photoconductors exhibit a discrimination ratio up to 108 between 210nm and visible light. The spectral responsivity at 220nm is about 6A∕W biased at 3V, corre…
Li-doped ZnO films were prepared by pulsed laser deposition. The carrier type could be controlled by adjusting the growth conditions. In an ionized oxygen atmosphere, p-type ZnO was achieved, with the hole concentration of 6.04×1017cm−3 at an optimal Li content of 0.6at.%, whereas ZnO exhibited n-type conductivity in…
We study electron correlation effects on quantum criticalities of Lifshitz transitions at zero temperature, using the mean-field theory based on a preexisting symmetry-broken order, in two-dimensional systems. In the presence of interactions, Lifshitz transitions may become discontinuous in contrast to the continuous…
The authors have quantified the quenching of the luminescence lifetime of Er3+ ions in organic complexes due to the presence of CH vibrational oscillators as a function of their distance from the ion. They have shown that any hydrogen atoms within a sphere of at least 20Å from an erbium ion will cause sufficient quenc…
Three kinds of the response mechanisms to the external pressure have been found for double-walled carbon nanotube (DWCNT) bundle, depending strongly on their average radius and symmetry. The small-diameter DWCNT bundle undergoes a small discontinuous volume change, and then deform continuously. The intermediate-diamet…
This chapter discusses incommensurate and commensurate modulated structures. After an introduction to the concepts used to describe modulated structures, including the basic ideas of higher-dimensional crystallography, four-dimensional space groups and displacive and occupational modulation, superspace-group determina…
The authors show using atomistic simulations that stress-driven grain growth can be obtained in the athermal limit during nanocrystalline aluminum indentation. They find that the grain growth results from rotation of nanograins and propagation of shear bands. Together, these mechanisms are shown to lead to the unstabl…
High yield hausmannite (Mn 3 O 4 ) nanorods with diameters of about 100 nm and lengths up to 15–20 µm have been prepared by vacuum calcining of the precursor (Mn 3 O 4 +MnOOH), which was hydrothermally prepared by the reaction of PEG-20000 and KMnO 4 at 180 °C for 20 h. Transmission electron microscopy and the selecte…
In 1998, members of the Research Collaboratory for Structural Bioinformatics became the managers of the Protein Data Bank archive. This chapter details the systems used for the deposition, annotation and distribution of the data in the archive. Keywords: databases; nuclear magnetic resonance; NMR; Protein Data Bank; s…
A simple and highly reproducible single electron transistor (SET) has been fabricated using gated silicon nanowires. The structure is a metal-oxide-semiconductor field-effect transistor made on silicon-on-insulator thin films. The channel of the transistor is the Coulomb island at low temperature. Two silicon nitride…
Novel superconducting compounds such as the high Tc oxides are intrinsically inhomogeneous systems. An inhomogeneous structure is created by doping and the statistical nature of the distribution of dopants. Consequently, the critical temperature is spatially dependent: Tc = Tc (r).
We identify a class of covalent functionalizations that preserve or control the conductance of single-walled metallic carbon nanotubes. [2+1] cycloadditions can induce bond cleaving between adjacent sidewall carbons, recovering in the process the sp;{2} hybridization and the ideal conductance of the pristine tubes. Th…
The authors report on the resistivity of submicron copper lines ranging from 75to500nm linewidths as a function of temperature in the 10Kto380K interval. Their estimate of the contributions to electron scattering at 20K for the narrowest line (75nm linewidth) is 29% from copper surfaces, 25% from grain boundaries, and…
The tunnel magnetoresistance (TMR) effect has been investigated for magnetic tunnel junctions with epitaxial Co2FeAl0.5Si0.5 Heusler electrodes with B2 and L21 structures on a Cr-bufferd MgO substrate. The epitaxially grown Co2FeAl0.5Si0.5 has B2 structure when annealed below 400°C, and has L21 structure for annealing…